(a) Field of the Invention
This invention generally relates to a water waste prevention device for a water closet having a reservoir tank and a bowl, and more particularly, but not by way of limitation, to an attachment for a fill tube in a water closet for preventing the waste of water by increasing the efficiency of the water closet's use of water, and more particularly to a device for enhancing the efficiency of a water closet by diverting excess water flow into the water closet's reservoir tank instead of into the bowl.
(b) Discussion of the Prior Art
One of the most common designs for water closets includes a bowl which serves as a receptacle for receiving waste and is in fluid communication with a sewer line. Common designs for water closets also include a water reservoir tank, the reservoir tank holds the water that is to be used for carrying waste from the bowl and into the sewer line, as well as for refilling the bowl.
The bowl is normally in fluid communication with the sewer line by means of a curved exit path commonly referred to as a trap. The trap is simply an "S" shaped duct having a high point that serves to limit the amount of water to be held in the bowl and to provide a siphon for drawing the waste out of the bowl. In operation, to flush waste out of the bowl, water from the reservoir tank is released into the bowl. This raises the level of the water in the bowl, which will exceed the level of the high point of the trap. When the level of the water in the bowl exceeds the level of the high point of the trap, the water in the bowl flows over the high point of the trap, towards the sewer line. The flow over the high point of the trap also initiates a siphoning effect that helps draw out the waste within the bowl, and thus helps completely flush out the waste and nearly completely empty the water within the bowl.
Once the water from the reservoir has been used to flush the waste the bowl, the reservoir tank must then be refilled. The tank is refilled with water from an external water source, such as a water line from the building's potable water system. Inside the reservoir tank a fill control mechanism which includes a valve attached to a float is typically used to control the refilling of the reservoir tank with the water from the external source. As is well known, the float rises as the water level in the tank rises. As the float rises, the float continuously closes the valve, so that the valve is completely closed by the float when a desired level of water is achieved in the tank.
During the flushing cycle, once the waste has been flushed from the bowl, the bowl must be gradually refilled with water from external water source, which must be added to the reservoir tank. It is important to gradually refill the bowl because if the bowl is filled rapidly the water in the bowl can momentarily exceed the high point of the trap, which will in turn induce a siphoning effect in the trap. A siphoning effect in the trap will once again draw out and flush the water from the bowl.
The design of the reservoir tank's fill mechanism provides safeguards against overfilling the reservoir tank. To prevent the overflow of the reservoir tank, an overflow tube which is in fluid communication with the bowl is provided within the reservoir tank. The overflow tube extends vertically from the bottom of the reservoir tank and has an opening at a height that establishes the maximum fill level of the reservoir tank. The overflow tube is in fluid communication with the bowl, and thus allows excess water that may be delivered into the reservoir tank to overflow into the overflow tube and into the bowl.
To fill the bowl after a flush, a fill tube is branched from the valve and extended to the opening of the overflow tube. This allows water from the external source to be diverted into the overflow tube instead of remaining in the reservoir tank. Once the water from the fill tube enters the overflow tube it then flows into the bowl. Thus, the valve continuously feeds water into the bowl while the reservoir tank is being refilled.
Thus, the typical fill system for a water closet advantageously uses one valve to control both the filling of the reservoir tank and the bowl. The simplicity of this design has made this a very popular arrangement in many, if not most, household installations. However, the fact that one valve controls the filling of both the reservoir tank and the bowl has serious drawbacks in that it results in the waste of thousands of gallons of treated potable water throughout the country every year. The waste stems from the fact that it takes much more water to fill the reservoir tank than to fill the bowl. Therefore, the valve remains open, filling the reservoir tank, for much longer than is required to fill the bowl through the fill tube and the overflow tube. The result is that water continues to enters the overflow tube from the fill tube and is then delivered to the bowl after the level of water in the bowl has reached the level of the high point of the trap. The excess water that enters the bowl is simply allowed to flow over the high point of the trap where it is discarded into the sewer line.
Because of the seriousness of the resulting waste of potable water, there have been many attempts to correct this problem. Since many of the water closets now in use have the wasteful system in place, many of the attempts at solving this problem are retrofits or modifications to the existing systems. These remedial or retrofit systems have the advantage that they do not require radical modifications to, or waste of, existing installations. For example, U.S. Pat. No. 2,807,024 to Kapp teaches that by placing a close ended (blind) tube in parallel to the overflow tube and by leading the fill tube into the parallel tube one may use the parallel tube as a ballast or reservoir for controlling the amount of water that eventually overflows from the parallel tube into the overflow tube. This device is disadvantaged, however, in that it can be noisy. The Kapp device allows water to drip out of a weep hole and into the reservoir tank. This dripping can be annoying and undesirable. Also, the parallel tube will always contain an amount of stagnant water, which can serve as an incubator for organic matter which would eventually accelerate the staining of the bowl with organic matter. Moreover, the Kapp device uses many relatively large parts which can result in increased manufacturing and inventorying costs.
In yet another example, U.S. Pat. No. 3,086,546 to Brown a combined water saving and silencing device is taught. The Brown device uses both a plurality of tubes to carry the water into the reservoir tank quietly and a threaded adjustable flow restrictor. The flow restrictor screws into the fill tube fluid passage and reduces the flow path to the fill tube. This arrangement is disadvantaged however in that it requires many parts and can thus be cumbersome to install and maintain. Also, the threaded flow restriction requires that the installer thread and manually adjust the flow past the restriction. This type of installation is disadvantaged in that it is labor intensive and can produce nonuniform results due to installer judgement error.
U.S. Pat. No. 4,145,775 to Butler presents yet another attempt at solving the problems associated with the waste of water during the filling of the reservoir tank. The Butler invention teaches the installation of a flow restrictor in the fill tube. The flow restrictor comprises of a two piece valve that permits adjustment of the flow path by rotating each piece relative to each other. While this device can be effective in restricting the flow through the fill tube it also suffers from limitations. The device's two piece construction is vulnerable to leaks, which can be especially noisy. Also, the valve requires manual adjustment by the installer, and thus is susceptible to installer error or negligence in setting the flow path at the optimal setting.
In yet another example of water saving devices, U.S. Pat. No. 4,449,259 to Davies et al., a one piece metering device which receives and accumulates water from the fill tube is taught. The metering device has a small orifice that permits accumulated water to seep out and into the overflow tube. This device offers advantages in that it is a one piece device, it does restrict the amount of water entering the overflow tube, it does not affect the function of the existing installation and does not require modifications to the existing installation. However, the Davies device also suffers from several limitations in that excess water just overflows the device and drips into the reservoir tank creating noise. Also, the Daives device is relatively large, and thus requires more raw material in fabrication. Also, in certain applications the device may experience difficulties supplying enough water to fill the bowl while maintaining a small enough flow through its flow orifice to effect any significant water savings.
Still other approaches at the problem of wasting water include U.S. Pat. No. 4,764,996 to Pino, which discloses the use of a graduated pinch clamp to restrict the path through the fill tube; U.S. Pat. No. 4,980,932 to Stempies, which teaches the use of a double ballcock flow splitting valve to divide the flow from the fill tube; and U.S. Pat. No. 5,134,729 to Shaw, which teaches the use of a metering device and a flow diverting elbow, and which requires the replacement of almost all of the internal devices of the reservoir tank and adds many parts to achieve a working apparatus.
Another example of devices for reducing the waste of water while refilling the reservoir tank is U.S. Pat. No. 5,287,565 to Auman et al. The Auman patent teaches the use of a small plastic insert with a generally square cross section and a generally rectangular body that serves as a manifold for several exit outlet tubes. The Auman device receives water from the fill tube in its rectangular body which evenly distributes the water over several exit tubes. The user directs the flow of a desired number of exit tubes into the overflow tube and allows the balance of the tubes to spill into the overflow tank. The rectangular body of the Auman invention offers a flow path that presents an expanded cavity with a cross-section that is larger than the cross-section of the flow path (wetted area) of the fill tube. This expanded cavity allows even dispersion into exit tubes through openings that are of the same size. The Auman device is designed to reduce the pressure from the fill line by providing an expanded cavity that acts as a plenum that evenly distributes the water over the ports that lead to the exit tubes. The user determines which of the exit tubes are to empty into the overflow tube and which tubes spill into the overflow tank. This arrangement is disadvantaged in that it is noisy because the many tubes that empty into the reservoir tank spill directly on to the water within the tank, and thus can produce splashing noises. Moreover, the header or plenum design tends to slow the exiting streams to the point where it becomes less likely that the streams will be fully and evenly distributed when entering the bowl. This lack of velocity and dispersion on entering the bowl can lead malfunctions and to uneven rinsing of the bowl with each flush. Still further, the lack of velocity and dispersion can lead to quicker staining of the bowl by minerals deposited by the water.
There remains, therefore, a need for a simple device for reducing the water wastage during the filling of the reservoir tank. Importantly, there remains a need for a simple device that uses few parts and that can be used with existing water closet installations, regardless of the manufacturer.
Moreover, there remains a need for a water closet water saving device that is reliable, easy to install and that does not require special skills to achieve optimal or desired results. Also, there remains a need for a simple, effective, quiet apparatus for reducing the waste of water during the filling of the reservoir tank of a water closet.